How to Use Resin Molds: Remove any dust and particles from your reusable mold. Molds do not require mold release when casting with resin, however, it is strongly suggested. We recommend the use of Castin' Craft Mold Release and Conditioner. Protect your work area with freezer or wax paper. Treat mold with mold release and allow to dry. Place mold on a level surface and fill the cavities to just below the top. Once the pieces are cured, turn the tray over and press the center area of each piece while flexing to release the casting. Do not use sharp objects to demold your resin as you will scratch your mold. Be sure to also read our plastic resin mold care tips to ensure a long life for your molds.